Electric terminal blocks



March 7, 1967 A. .1. R. WHITE ELECTRIC TERMINAL BLOCKS 2 Sheets-Sheet 1 Filed Feb. 19, 1965 //VVENTOR Hus/en Jess/w P/cHMo/vo 14/11/75,

March 7, 1967 A. J. R. WHITE ELECTRIC TERMINAL BLOCKS 2 Sheets-Sheet 2 Filed Feb. 19, 1965 /NVNTOR lizumev JOSEPH Plclmo/va Will TE.

HTT'Y.

United States Patent 3,308,421 ELECTRIC TERMINAL BLOCKS Aubrey Joseph Richmond White, Fulham Gardens, South Australia, Australia, assignor to Carr Fastener Pty. Ltd., a corporation of Australia Filed Feb. 19, 1965, Ser. No. 433,939 Claims priority, application Australia, Feb. 26, 1964, 41,336/ 64 2 Claims. (Cl. 339-196) This invention relates to electric terminal blocks of the kind comprising a body portion of insulating material, a plurality of terminal elements fixedly mounted in and projecting from one axial end of the insulating body, and terminal members electrically connected each to a respective terminal element and projecting from the opposite axial end of the insulating body, said members being spring-loaded and capable of limited axial movement towards the terminal element against said spring pressure.

Such terminal blocks are often used in motor vehicle lighting circuits and for many other various applications.

It is known to form the insulating body of such terminal blocks in two or more parts, in one of each parts the terminal elements are already mounted prior to assembly of the block itself. The springs may be of conventional helical variety receivable in cavities within the insulator. One end of each spring engages with a tail portion of the associated tab which protrudes rearwardly into the cavity, while over the other end may be placed the pin which is conveniently in the form of a cap having a radially outwardly extending flange around its marginal edge.

In the past, the various parts of such terminal blocks have usually been connected by screws or other fastening devices, and hence the blocks have generally required the use of tools for their assembly.

It is an object of this invention to simplify and expedite the assembly operation by providing a terminal block which is not dependent upon the use of tools for its assembly.

According to the present invention, an electric terminal block of the kind indicated is characterised in that the insulating body is formed in two parts from a resilient material, said parts being shaped complementarily with abutting surfaces having portions inclined to the axis of the block whereby the parts can be manually snapped into engagement in an axial direction and when thus eugaged, cannot readily be separated in an axial direction, said terminal members each having a radial abutment locating the relevant member with respect to a first of said body parts and functioning as a stop defining a normal extended position of the member under its spring pressure, a second of said parts defining apertures for receiving said terminal members thereby restraining sideways relative movement between the body parts.

But in order that the invention may be better understood, reference will now be made to the accompanying drawings which are to be considered as part of this specification and read herewith. In the drawings:

FIGURE 1 shows in perspective one preferred form of terminal block in accordance with this invention;

FIGURE 2 shows separately the two insulating body portions of the block illustrated in FIGURE 1;

FIGURES 3 and 4 show in like manner to FIGURE 2, two further embodiments of insulating body portions in accordance with the invention;

FIGURE 5 is a side elevation of the block of FIG- URES 1 and 2 prior to assembly;

FIGURE 6 is an axial section across line VIVI in FIGURE 5;

3,308,421 Patented Mar. 7, 1967 FIGURE 7 shows a plan view of a terminal tab as used in the block illustrated in FIGURES 1, 2, 5 and 6, and

FIGURE 8 is a broken-away perspective view of the block shown in FIGURES 1, 2 and 5 to 7.

The terminal block illustrated comprises an insulating body consisting of first and second parts 9 and 10 respectively formed from a resilient material the former having a pair of terminal elements in the form of tabs 11 fixedly mounted therein and projecting from a forward axial end of the body. Tabs 11 are of substantially planar formation, parallel and symmetrically disposed on either side of an axial plane of the terminal block. This plane may be considered to be parallel to the drawing when looking at FIGURE 5. Tabs 11 are electrically connected by way of conductive helical springs 12 to terminal members in the form of caps 13 projecting from the rearward axial end of the body, springs 12 rendering caps 13 capable of limited forward movement against the spring pressure.

Body parts 9 and 10 are of resilient material, the former defining a pair of rearwardly-opening parallel cylindrical cavities 14 having their axes substantially parallel to and symmetrically disposed on either side of the axial plane.

Tabs 11 each consist of a forward exposed portion 15 which is receivable in a socket or like fitting (not shown) and an enlarged portion 16 adapted for embedding in part 9 of the insulating body. Behind 16 is located a tail portion 17 and these last-mentioned portions 17 protrude into forward parts of the respective cavities 14 for engagement with springs 12. This engagement is assisted by providing the tabs with barbs or like abutments 18.

The second body part 10 defines a pair of apertures 19 substantially circular in cross-section and having their axes parallel to and symmetrically disposed on either side of an axis of part 10.

The rear end of each spring 12 is received in a cap 13 already referred to hereinabove, the caps being accommodated in apertures 19. Each cap has a radial abutment in the form of a flange 20 adapted to abut against a forward marginal edge of the relevant aperture.

According to the invention parts 9 and 10 are shaped complementarily (preferably in dove-tailed configuration various forms of which are illustrated in FIGURES 1 to 4) so that the parts can be manually snapped into coaxial engagement in a relative axial direction and when thus engaged, cannot readily or fortuitously be separated in an axial direction. It will further be evident that sub stantial sideways relative movement between parts 9 and 10 when engaged, will be prevented by the caps 13 in apertures 19.

To assemble the terminal block according to this invention, assuming the tabs 11 are already fitted within part 9, springs 12 are placed in position over the inner ends of the terminal tabs at the base of the respective cavities 14, and caps 13 are then placed on the free ends of the springs. Part 10 is now fitted in the direction shown by the arrow in FIGURE 6 such that the apex portions of the caps 13 pass through apertures 19 which, it will be appreciated, should be somewhat larger in diameter than the main portions of the caps 13 although less in diameter than flanges 20 associated with each cap. Parts 9 and 10 may then be pushed together with the caps 13 passing through apertures 19 in part 10, and the dove-tail portions snapped into engagement upon suitable deformation of the resilient material of which the insulator is formed.

The assembled terminal block then presents the appearance shown in FIGURE 1.

It will be evident from the foregoing that the invention allows of many modifications. Those illustrated are to be understood as by way of example only.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An electric terminal block of the kind indicated characterized in that the terminal elements consist of a pair of tabs of substantially planar formation mounted in and projecting forwardly from a first part of said insulating body, said tabs being substantially parallel and symmetrically disposed on either side of an axial plane of the terminal block, said first body part being of resilient material and defining a pair of rearwardly opening parallel cylindrical cavities having their axes substantially parallel to and symmetrically disposed on either side of the axial plane, said tabs having tail portions protruding into the forward end parts of the respective cavities, said insulating body further comprising a second part likewise of resilient material and defining a pair of apertures substantially circular in cross-section and having their axes parallel to and symmetrically disposed on either side of an axis of said second part, the block further comprising a pair of helical springs, one located in each said cavity and engaged at a forward end with the tail portion of the relevant tab, the other end of each spring being accommodated within a conductive cap, each cap being capable of being passed through one of said apertures and having a flange adapted to abut 4 against a forward marginal edge of the relevant aperture, said first and second body parts being formed in a complementary dove-tailed configuration whereby the parts can be manually snapped into coaxial engagementin a relative axial direction and when thus engaged, cannot readily or accidentally be separated in an axial direction, sideways relation movement between the engaged parts being restrained by said caps within their respective apertures.

2. An electric terminal block as claimed in claim 1 characterized in that each conductive tab consists of a forward exposed portion receivable in a socket within a fitting with which the block is to be engaged, immediately behind which forward portion is an enlarged portion adapted to be embedded in the first insulating body part, said tail portion being disposed behind the enlarged portion and having a barb assisting engagement with the associated spring member.

References Cited by the Examiner UNITED STATES PATENTS 3,183,475 5/1965 Meyer et al 339220 X 3,213,189 10/1965 Mitchell et al. 339128 X EDWARD C. ALLEN, Primary Examiner;

W. DONALD MILLER, Examiner. 

1. AN ELECTRIC TERMINAL BLOCK OF THE KIND INDICATED CHARACTERIZED IN THAT THE TERMINAL ELEMENTS CONSIST OF A PAIR OF TABS OF SUBSTANTIALLY PLANAR FORMATION MOUNTED IN AND PROJECTING FORWARDLY FROM A FIRST PART OF SAID INSULATING BODY, SAID TABS BEING SUBSTANTIALLY PARALLEL AND SYMMETRICALLY DISPOSED ON EITHER SIDE OF AN AXIAL PLANE OF THE TERMINAL BLOCK, SAID FIRST BODY PART BEING OF RESILIENT MATERIAL AND DEFINING A PAIR OF REARWARDLY OPENING PARALLEL CYLINDRICAL CAVITIES HAVING THEIR AXES SUBSTANTIALLY PARALLEL TO AND SYMMETRICALLY DISPOSED ON EITHER SIDE OF THE AXIAL PLANE, SAID TABS HAVING TAIL PORTIONS PROTRUDING INTO THE FORWARD END PARTS OF THE RESPECTIVE CAVITIES, SAID INSULATING BODY FURTHER COMPRISING A SECOND PART LIKEWISE OF RESILIENT MATERIAL AND DEFINING A PAIR OF APERTURES SUBSTANTIALLY CIRCULAR INCROSS-SECTION AND HAVING THEIR AXES PARALLEL TO AND SYMMETRICALLY DISPOSED ON EITHER SIDE OF AN AXIS OF SAID SECOND PART, THE BLOCK FURTHER COMPRISING A PAIR OF HELICAL SPRINGS, ONE LOCATED IN EACH SAID CAVITY AND ENGAGED AT A FORWARD END WITH THE TAIL PORTION OF THE RELEVANT TAB, THE OTHER END OF EACH SPRING BEING ACCOMMODATED WITHIN A CONDUCTIVE CAP, EACH CAP BEING CAPABLE OF BEING PASSED THROUGH ONE OF SAID APERTURES AND HAVING A FLANGE ADAPTED TO ABUT AGAINST A FORWARD MARGINAL EDGE OF THE RELEVANT APERTURE, SAID FIRST AND SECOND BODY PARTS BEING FORMED IN A COMPLEMENTARY DOVE-TAILED CONFIGURATION WHEREBY THE PARTS CAN BE MANUALLY SNAPPED INTO COAXIAL ENGAGEMENT IN A RELATIVE AXIAL DIRECTION AND WHEN THUS ENGAGED, CANNOT READILY OR ACCIDENTALLY BE SEPARATED IN AN AXIAL DIRECTION, SIDEWAYS RELATION MOVEMENT BETWEEN THE ENGAGED PARTS BEING RESTRAINED BY SAID CAPS WITHIN THEIR RESPECTIVE APERTURES. 